This invention relates to a solid state image sensing apparatus and in particular to a solid state image sensor used for an electronic still camera.
A solid state image sensor is used for a television camera, etc. In the television camera, a number of photoelectric elements which are arranged in a matrix array are scanned by vertical and horizontal scanning signals to pick up image signals from the solid state image sensor. Where the brightness of a subject is to be measured by the solid state image sensor before it is photographed, the solid state image sensor matrix is scanned, as in an image pick-up operation, by horizontal and vertical scanning signals and the amount of light on the subject is measured on the basis of image signals obtained by the scanning operation. Where the brightness of a specific portion of the subject is to be measured according to such a photometric system, it is possible to effect only one photometric operation for each single scanning period. There is a problem, then, with the speed at which such a photometic operation can be performed. Furthermore, it is not possible to simultaneously measure the brightness of a plurality of specific portions of the subject.